1
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'Quantum internet' demonstration in cities is most advanced yet. Nature 2024; 629:734-735. [PMID: 38750204 DOI: 10.1038/d41586-024-01445-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
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2
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Intel brings quantum-computing microchips a step closer. Nature 2024; 629:50-51. [PMID: 38693404 DOI: 10.1038/d41586-024-01208-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
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3
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Topological matter created on a quantum chip produces quasiparticles with computing power. Nature 2024:10.1038/d41586-023-04126-8. [PMID: 38355993 DOI: 10.1038/d41586-023-04126-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
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4
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Mobile atoms enable efficient computation with logical qubits. Nature 2024; 626:36-38. [PMID: 38287183 DOI: 10.1038/d41586-024-00075-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
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5
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Who needs qubits? Physicists make light-based 'qumodes' for quantum computing. Nature 2024; 626:11. [PMID: 38287157 DOI: 10.1038/d41586-024-00179-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
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6
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Engineering multimode interactions in circuit quantum acoustodynamics. NATURE PHYSICS 2024; 20:564-570. [PMID: 38638458 PMCID: PMC11021184 DOI: 10.1038/s41567-023-02377-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 12/13/2023] [Indexed: 04/20/2024]
Abstract
In recent years, important progress has been made towards encoding and processing quantum information in the large Hilbert space of bosonic modes. Mechanical resonators have several practical advantages for this purpose, because they confine many high-quality-factor modes into a small volume and can be easily integrated with different quantum systems. However, it is challenging to create direct interactions between different mechanical modes that can be used to emulate quantum gates. Here we demonstrate an in situ tunable beamsplitter-type interaction between several mechanical modes of a high-overtone bulk acoustic-wave resonator. The engineered interaction is mediated by a parametrically driven superconducting transmon qubit, and we show that it can be tailored to couple pairs or triplets of phononic modes. Furthermore, we use this interaction to demonstrate the Hong-Ou-Mandel effect between phonons. Our results lay the foundations for using phononic systems as quantum memories and platforms for quantum simulations.
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7
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The AI-quantum computing mash-up: will it revolutionize science? Nature 2024:10.1038/d41586-023-04007-0. [PMID: 38167658 DOI: 10.1038/d41586-023-04007-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
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8
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A quantum fix makes e-commerce more tamper-resistant. Nature 2024; 625:635. [PMID: 38228933 DOI: 10.1038/d41586-024-00128-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
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9
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Resource-efficient fault-tolerant one-way quantum repeater with code concatenation. NPJ QUANTUM INFORMATION 2023; 9:123. [PMID: 38665254 PMCID: PMC11041798 DOI: 10.1038/s41534-023-00792-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 11/22/2023] [Indexed: 04/28/2024]
Abstract
One-way quantum repeaters where loss and operational errors are counteracted by quantum error-correcting codes can ensure fast and reliable qubit transmission in quantum networks. It is crucial that the resource requirements of such repeaters, for example, the number of qubits per repeater node and the complexity of the quantum error-correcting operations are kept to a minimum to allow for near-future implementations. To this end, we propose a one-way quantum repeater that targets both the loss and operational error rates in a communication channel in a resource-efficient manner using code concatenation. Specifically, we consider a tree-cluster code as an inner loss-tolerant code concatenated with an outer 5-qubit code for protection against Pauli errors. Adopting flag-based stabilizer measurements, we show that intercontinental distances of up to 10,000 km can be bridged with a minimized resource overhead by interspersing repeater nodes that each specialize in suppressing either loss or operational errors. Our work demonstrates how tailored error-correcting codes can significantly lower the experimental requirements for long-distance quantum communication.
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Grants
- NWO Gravitation Program Quantum Software Consortium - QSC024.003.037
- ARO(W911NF-23-1-0077), ARO MURI (W911NF-21-1-0325), AFOSR MURI (FA9550-19-1-0399, FA9550-21-1-0209), AFRL (FA8649- 21-P-0781), NSF (OMA-1936118, ERC-1941583, OMA-2137642), NTT Research, Packard Foundation (2020-71479), and the Marshall and Arlene Bennett Family Research Program.
- Austrian Science Fund (Fonds zur Förderung der Wissenschaftlichen Forschung)
- Finanziert von der Europäischen Union - NextGenerationEU
- Bundesministerium für Bildung und Forschung (Federal Ministry of Education and Research)
- European Research Council (ERC Starting Grant "QUREP")
- Danish Nation Research Foundation (Center of Excellence "Hy-Q," Grant No. DNRF139)
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10
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Probing single electron spins with an atomic force microscope for quantum applications. Nature 2023:10.1038/d41586-023-03650-x. [PMID: 38057463 DOI: 10.1038/d41586-023-03650-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
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11
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Keeping secrets in a quantum world. Nature 2023; 623:S1-S3. [PMID: 37914949 DOI: 10.1038/d41586-023-03336-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
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12
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New kind of quantum computer made using high-resolution microscope. Nature 2023:10.1038/d41586-023-03141-z. [PMID: 37803200 DOI: 10.1038/d41586-023-03141-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/08/2023]
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13
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Magnetic atoms push interactions to new lengths for quantum simulation. Nature 2023; 622:704-705. [PMID: 37880434 DOI: 10.1038/d41586-023-03152-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
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14
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Abstract
The QBIT theory is a recently introduced multi-disciplinary approach to the problem of consciousness. One of the main axioms of the theory is that when information-theoretic certainty of an observer about a stimulus goes beyond a certain threshold, the observer becomes conscious of that stimulus. This axiom could provide an explanation for how the brain generates consciousness.In short, the QBIT theory suggests that the brain generates consciousness by reducing the entropy of its internal representations below a critical threshold. This paper explains how the brain gradually minimizes the entropy of its internal representations and consequently generate minimum-entropy representations (also known as conscious representations or qualia). The paper also explores the consequences of this entropy-minimization process in the context of quantum information theory.
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15
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Quantum reference frames for an indefinite metric. COMMUNICATIONS PHYSICS 2023; 6:231. [PMID: 38665408 PMCID: PMC11041732 DOI: 10.1038/s42005-023-01344-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 08/10/2023] [Indexed: 04/28/2024]
Abstract
The current theories of quantum physics and general relativity on their own do not allow us to study situations in which the gravitational source is quantum. Here, we propose a strategy to determine the dynamics of objects in the presence of mass configurations in superposition, and hence an indefinite spacetime metric, using quantum reference frame (QRF) transformations. Specifically, we show that, as long as the mass configurations in the different branches are related via relative-distance-preserving transformations, one can use an extension of the current framework of QRFs to change to a frame in which the mass configuration becomes definite. Assuming covariance of dynamical laws under quantum coordinate transformations, this allows to use known physics to determine the dynamics. We apply this procedure to find the motion of a probe particle and the behavior of clocks near the mass configuration, and thus find the time dilation caused by a gravitating object in superposition. Comparison with other models shows that semi-classical gravity and gravitational collapse models do not obey the covariance of dynamical laws under quantum coordinate transformations.
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16
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Surpassing spectator qubits with photonic modes and continuous measurement for Heisenberg-limited noise mitigation. NPJ QUANTUM INFORMATION 2023; 9:81. [PMID: 38726362 PMCID: PMC11080661 DOI: 10.1038/s41534-023-00748-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 07/25/2023] [Indexed: 05/12/2024]
Abstract
Noise is an ever-present challenge to the creation and preservation of fragile quantum states. Recent work suggests that spatial noise correlations can be harnessed as a resource for noise mitigation via the use of spectator qubits to measure environmental noise. In this work we generalize this concept from spectator qubits to a spectator mode: a photonic mode which continuously measures spatially correlated classical dephasing noise and applies a continuous correction drive to frequency-tunable data qubits. Our analysis shows that by using many photon states, spectator modes can surpass many of the quantum measurement constraints that limit spectator qubit approaches. We also find that long-time data qubit dephasing can be arbitrarily suppressed, even for white noise dephasing. Further, using a squeezing (parametric) drive, the error in the spectator mode approach can exhibit Heisenberg-limited scaling in the number of photons used. We also show that spectator mode noise mitigation can be implemented completely autonomously using engineered dissipation. In this case no explicit measurement or processing of a classical measurement record is needed. Our work establishes spectator modes as a potentially powerful alternative to spectator qubits for noise mitigation.
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17
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Could the Universe be a giant quantum computer? Nature 2023; 620:943-945. [PMID: 37626174 DOI: 10.1038/d41586-023-02646-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2023]
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18
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A fast quantum route to random numbers. Nature 2023; 619:256-257. [PMID: 37438597 DOI: 10.1038/d41586-023-02176-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
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19
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How to introduce quantum computers without slowing economic growth. Nature 2023; 619:461-464. [PMID: 37460723 DOI: 10.1038/d41586-023-02317-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
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20
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IBM quantum computer passes calculation milestone. Nature 2023:10.1038/d41586-023-01965-3. [PMID: 37316602 DOI: 10.1038/d41586-023-01965-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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21
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Quantum computer scales up by mitigating errors. Nature 2023; 618:462-463. [PMID: 37316716 DOI: 10.1038/d41586-023-01884-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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22
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Particle, wave, both or neither? The experiment that challenges all we know about reality. Nature 2023; 618:454-456. [PMID: 37311956 DOI: 10.1038/d41586-023-01938-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
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23
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Commercializing quantum computers step by step. Nature 2023:10.1038/d41586-023-01644-3. [PMID: 37225802 DOI: 10.1038/d41586-023-01644-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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24
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Towards quantum machine learning. Nature 2023:10.1038/d41586-023-01718-2. [PMID: 37253982 DOI: 10.1038/d41586-023-01718-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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25
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Rewriting the quantum-computer blueprint. Nature 2023:10.1038/d41586-023-01660-3. [PMID: 37225814 DOI: 10.1038/d41586-023-01660-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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26
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Physicists create long-sought topological quantum states. Nature 2023; 617:445-446. [PMID: 37160988 DOI: 10.1038/d41586-023-01574-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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27
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Optimal entanglement distribution policies in homogeneous repeater chains with cutoffs. NPJ QUANTUM INFORMATION 2023; 9:46. [PMID: 38665258 PMCID: PMC11041801 DOI: 10.1038/s41534-023-00713-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 04/17/2023] [Indexed: 04/28/2024]
Abstract
We study the limits of bipartite entanglement distribution using a chain of quantum repeaters that have quantum memories. To generate end-to-end entanglement, each node can attempt the generation of an entangled link with a neighbor, or perform an entanglement swapping measurement. A maximum storage time, known as cutoff, is enforced on the memories to ensure high-quality entanglement. Nodes follow a policy that determines when to perform each operation. Global-knowledge policies take into account all the information about the entanglement already produced. Here, we find global-knowledge policies that minimize the expected time to produce end-to-end entanglement. Our methods are based on Markov decision processes and value and policy iteration. We compare optimal policies to a policy in which nodes only use local information. We find that the advantage in expected delivery time provided by an optimal global-knowledge policy increases with increasing number of nodes and decreasing probability of successful swapping.
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28
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29
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Superconducting qubits cover new distances. Nature 2023; 617:254-256. [PMID: 37165233 DOI: 10.1038/d41586-023-01488-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
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30
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Scalable set of reversible parity gates for integer factorization. COMMUNICATIONS PHYSICS 2023; 6:73. [PMID: 38665406 PMCID: PMC11041783 DOI: 10.1038/s42005-023-01191-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/31/2023] [Indexed: 04/28/2024]
Abstract
Classical microprocessors operate on irreversible gates, that, when combined with AND, half-adder and full-adder operations, execute complex tasks such as multiplication of integers. We introduce parity versions of all components of a multiplication circuit. The parity gates are reversible quantum gates based on the recently introduced parity transformation and build on ground-space encoding of the corresponding gate logic. Using a quantum optimization heuristic, e.g., an adiabatic quantum computing protocol, allows one to quantum mechanically reverse the process of multiplication and thus factor integers, which has applications in cryptography. Our parity approach builds on nearest-neighbor constraints equipped with local fields, able to encode the logic of a binary multiplication circuit in a modular and scalable way.
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31
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Scalable quantum processors empowered by the Fermi scattering of Rydberg electrons. COMMUNICATIONS PHYSICS 2023; 6:57. [PMID: 38665413 PMCID: PMC11041703 DOI: 10.1038/s42005-023-01174-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 03/16/2023] [Indexed: 04/28/2024]
Abstract
Quantum computing promises exponential speed-up compared to its classical counterpart. While the neutral atom processors are the pioneering platform in terms of scalability, the dipolar Rydberg gates impose the main bottlenecks on the scaling of these devices. This article presents an alternative scheme for neutral atom quantum processing, based on the Fermi scattering of a Rydberg electron from ground-state atoms in spin-dependent lattice geometries. Instead of relying on Rydberg pair-potentials, the interaction is controlled by engineering the electron cloud of a sole Rydberg atom. The present scheme addresses the scaling obstacles in Rydberg processors by exponentially suppressing the population of short-lived states and by operating in ultra-dense atomic lattices. The restoring forces in molecule type Rydberg-Fermi potential preserve the trapping over a long interaction period. Furthermore, the proposed scheme mitigates different competing infidelity criteria, eliminates unwanted cross-talks, and significantly suppresses the operation depth in running complicated quantum algorithms.
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32
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Fast single-photon detectors and real-time key distillation enable high secret-key-rate quantum key distribution systems. NATURE PHOTONICS 2023; 17:422-426. [PMID: 37162797 PMCID: PMC10162938 DOI: 10.1038/s41566-023-01168-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 01/30/2023] [Indexed: 05/11/2023]
Abstract
Quantum key distribution has emerged as the most viable scheme to guarantee information security in the presence of large-scale quantum computers and, thanks to the continuous progress made in the past 20 years, it is now commercially available. However, the secret key rates remain limited to just over 10 Mbps due to several bottlenecks on the receiver side. Here we present a custom multipixel superconducting nanowire single-photon detector that is designed to guarantee high count rates and precise timing discrimination. Leveraging the performance of the detector and coupling it to fast acquisition and real-time key distillation electronics, we remove two major roadblocks and achieve a considerable increase of the secret key rates with respect to the state of the art. In combination with a simple 2.5-GHz clocked time-bin quantum key distribution system, we can generate secret keys at a rate of 64 Mbps over a distance of 10.0 km and at a rate of 3.0 Mbps over a distance of 102.4 km with real-time key distillation.
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33
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Towards quantum computers that are robust to errors. Nature 2023:10.1038/d41586-022-04532-4. [PMID: 36814016 DOI: 10.1038/d41586-022-04532-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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34
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Google's quantum computer hits key milestone by reducing errors. Nature 2023:10.1038/d41586-023-00536-w. [PMID: 36814025 DOI: 10.1038/d41586-023-00536-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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35
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Deterministic improvements of quantum measurements with grouping of compatible operators, non-local transformations, and covariance estimates. NPJ QUANTUM INFORMATION 2023; 9:14. [PMID: 38665255 PMCID: PMC11041696 DOI: 10.1038/s41534-023-00683-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/11/2023] [Indexed: 04/28/2024]
Abstract
Obtaining the expectation value of an observable on a quantum computer is a crucial step in the variational quantum algorithms. For complicated observables such as molecular electronic Hamiltonians, one of the strategies is to present the observable as a linear combination of measurable fragments. The main problem of this approach is a large number of measurements required for accurate estimation of the observable's expectation value. We consider three previously studied directions that minimize the number of measurements: (1) grouping commuting operators using the greedy approach, (2) involving non-local unitary transformations for measuring, and (3) taking advantage of compatibility of some Pauli products with several measurable groups. The last direction gives rise to a general framework that not only provides improvements over previous methods but also connects measurement grouping approaches with recent advances in techniques of shadow tomography. Following this direction, we develop two measurement schemes that achieve a severalfold reduction in the number of measurements for a set of model molecules compared to previous state-of-the-art methods.
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36
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Deterministic generation of indistinguishable photons in a cluster state. NATURE PHOTONICS 2023; 17:324-329. [PMID: 37064524 PMCID: PMC10091623 DOI: 10.1038/s41566-022-01152-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/19/2022] [Indexed: 06/19/2023]
Abstract
Entanglement between particles is a basic concept of quantum sciences. The ability to produce entangled particles in a controllable manner is essential for any quantum technology. Entanglement between light particles (photons) is particularly crucial for quantum communication due to light's non-interactive nature and long-lasting coherence. Resources producing entangled multiphoton cluster states will enable communication between remote quantum nodes, as the inbuilt redundancy of cluster photons allows for repeated local measurements-compensating for losses and probabilistic Bell measurements. For feasible applications, the cluster generation should be fast, deterministic and, most importantly, its photons indistinguishable, which will allow measurements and fusion of clusters by interfering photons. Here, using periodic excitation of a semiconductor quantum-dot-confined spin, we demonstrate a multi-indistinguishable photon cluster, featuring a continuously generated string of photons at deterministic gigahertz generation rates, and an optimized entanglement length of about ten photons. The indistinguishability of the photons opens up new possibilities for scaling up the cluster's dimensionality by fusion, thus building graph states suited for measurement-based photonic quantum computers and all-photonic quantum repeaters.
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37
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Underdog technologies gain ground in quantum-computing race. Nature 2023; 614:400-401. [PMID: 36747100 DOI: 10.1038/d41586-023-00278-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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38
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Approaching optimal entangling collective measurements on quantum computing platforms. NATURE PHYSICS 2023; 19:351-357. [PMID: 36942094 PMCID: PMC10020085 DOI: 10.1038/s41567-022-01875-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 11/08/2022] [Indexed: 06/18/2023]
Abstract
Entanglement is a fundamental feature of quantum mechanics and holds great promise for enhancing metrology and communications. Much of the focus of quantum metrology so far has been on generating highly entangled quantum states that offer better sensitivity, per resource, than what can be achieved classically. However, to reach the ultimate limits in multi-parameter quantum metrology and quantum information processing tasks, collective measurements, which generate entanglement between multiple copies of the quantum state, are necessary. Here, we experimentally demonstrate theoretically optimal single- and two-copy collective measurements for simultaneously estimating two non-commuting qubit rotations. This allows us to implement quantum-enhanced sensing, for which the metrological gain persists for high levels of decoherence, and to draw fundamental insights about the interpretation of the uncertainty principle. We implement our optimal measurements on superconducting, trapped-ion and photonic systems, providing an indication of how future quantum-enhanced sensing networks may look.
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39
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Are quantum computers about to break online privacy? Nature 2023; 613:221-222. [PMID: 36609552 DOI: 10.1038/d41586-023-00017-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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40
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Did physicists create a wormhole in a quantum computer? Nature 2022; 612:201-202. [PMID: 36456822 DOI: 10.1038/d41586-022-04201-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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41
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Driven quantum bits push computational limit. Nature 2022; 612:217-218. [PMID: 36477126 DOI: 10.1038/d41586-022-04168-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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42
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Virtual library of LSD-like drugs could reveal new antidepressants. Nature 2022:10.1038/d41586-022-03185-7. [PMID: 36198826 DOI: 10.1038/d41586-022-03185-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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43
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'Spooky' quantum-entanglement experiments win physics Nobel. Nature 2022; 610:241-242. [PMID: 36195711 DOI: 10.1038/d41586-022-03088-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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44
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AlphaFold developers win US$3-million Breakthrough Prize. Nature 2022; 609:889. [PMID: 36138210 DOI: 10.1038/d41586-022-02999-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hybrid laser-trapping technique lights the way for neutral atoms. Nature 2022; 609:898-900. [PMID: 36163466 DOI: 10.1038/d41586-022-02953-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Quantum memories entangled over tens of kilometres of optical fibre. Nature 2022:10.1038/d41586-022-01554-w. [PMID: 35794380 DOI: 10.1038/d41586-022-01554-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Loops simplify a set-up to boost quantum computational advantage. Nature 2022; 606:31-32. [PMID: 35650360 DOI: 10.1038/d41586-022-01402-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Quantum microphone is a leap ahead of the competition. Nature 2022; 606:843. [PMID: 35732722 DOI: 10.1038/d41586-022-01709-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Breakthrough in teleportation furthers quantum network development. Nature 2022; 605:624-625. [PMID: 35614238 DOI: 10.1038/d41586-022-01364-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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